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Topic Review (Newest First)

03-09-2011 09:41 PM

Paul P

You are ok with 4V max.

Here is the formula From SCT

This is the start of the Formula: (Volts*X)+Y
 We take the A/F equal to 0 volts to figure out the Y.
 We take the A/F equal to Max Volts to Figure out the X.
Here is an Example:
 (V*X)+Y
 0 Volts = 10/1 AFR.  Lets Call this Value1
 5 Volts = 18/1 AFR.  Lets Call this Value2
 (V*1.6)+10
To Figure Out Y: Y is always equal to Value1, so Y=10 in this example.
To Figure Out X: Take Value2 (18 in this example) and Minus Value1. So 18-10=8 in this
example. Then divide that number by the max volts. (5 in this example). 8/5=1.6.
Here is another Example:
 (V*X)+Y
 0 Volts = 10/1 AFR.  Lets Call this Value1
 5 Volts = 20/1 AFR.  Lets Call this Value2
 (V*2)+10

To do your gauge you need to set or know what the AFR is at 0V and 4V and you should be all set. If you know what they are post it and I'll help you with the formula.

Paul

03-08-2011 09:56 PM

Paul P

What you have only has a 0-4V scale from what I have been reading. The SCT XF3 needs an analog range of 0-5V. The other thing that is not defined is the range of AFR from 0-4V so if you can tell me that I might be able to figure it out. On the innovative MTX-L that I have it is 0V=7.35AFR and 5V=22.5 so the equation for this is (v*3.008)+7.35. I"ll check the SCT manual tomorrow for the equation formula.